Updated 10:52 p.m. | Former Gov. Mark Sanford will advance, as expected, to the Republican primary runoff on April 2.

With 100 percent of precincts reporting, Sanford took 37 percent, according to The Associated Press. That was enough to send him to a head-to-head matchup with another Republican, but not over the 50 percent threshold needed to win the nomination outright.

Sanford appears poised to face attorney Curtis Bostic, who received the second-highest number of votes.

But a recount loomed: Bostic, a former Charleston County councilman, led state Sen. Larry Groom by only 493 votes, or 0.92 percent of ballots cast.

Under South Carolina election law, if the margin separating two candidates is one point or less, an automatic recount takes place — unless the other candidate waives a recount in writing.

Grooms is not conceding and, as of Tuesday night, does not plan to waive a recount, Grooms strategist Hogan Gidley told CQ Roll Call.

Sanford, a staunch fiscal conservative, served three terms in the House before successfully running for governor. But in his second term as the Palmetto State’s chief executive, he gained national and international fame when he disappeared from the state for days in 2009 and then admitted to an extramarital affair with a woman from Argentina. He had told staff he was hiking the Appalachian Trail.

His disappearance is likely to be an issue in the two-week sprint to the runoff in a state where politics can often be a vicious bloodsport.